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K Zerres

Publications and source records attributed to K Zerres.

At least 37 records · Page 2Linked to original sources
PubMed2003

Classical infantile spinal muscular atrophy with SMN deficiency causes sensory neuronopathy.

OBJECTIVE: Classic infantile spinal muscular atrophy (SMA) is believed to be a purely motor disorder, affecting neurons of the spinal anterior horn and nuclei of the lower cranial nerves. Other organ malformations or peripheral nerve involvement have been regarded as exclusion criteria for infantile SMA. Whether SMN protein deficiency can also lead to loss of sensory neurons has not been systematically addressed. METHODS: The authors evaluated the sural nerve biopsies of 19 patients with infantile SMA of varying severity. The diagnosis of SMA was confirmed by the presence of a homozygous deletion of the SMN1 gene in all patients. RESULTS: In seven unrelated infants with SMA type I, axonal degeneration of the sural nerve was noted. Five patients showed abnormal sensory conduction, thus prompting sural nerve biopsy. Sural nerves showed different degrees of axonal loss: fiber density ranged from 3.482 to 22.076/mm2 and was markedly reduced in four patients. There was no evidence of primary demyelination: the ratio of total myelinated fiber thickness to axon diameter (g-ratio) was normal in the patients examined. In seven patients with SMA II and five patients with SMA III, no sural nerve alterations were seen, and conduction velocity was normal. In addition to SMN1 gene deletions, homozygous NAIP gene deletions were detected in six out of seven infants with peripheral neuropathy, whereas there was no evidence of a large deletion including the multicopy markers C212 and Ag1-CA in two out of three families tested. CONCLUSIONS: In this series of patients with SMA I through III who underwent sural nerve biopsy, there was significant sensory nerve pathology in severely affected patients with SMA type I, whereas there were no sensory nerve alterations clinically or morphologically in patients with milder SMA type II or III.

Axons↗
PubMed2003

[Psychiatric and ethical aspects of genetic diagnosis exemplified by Huntington chorea].

Huntington's disease is an autosomally dominant, inherited neurodegenerative disorder. Depression, psychotic syndromes, and personality changes are common psychiatric features, frequently occurring before the onset of characteristic motor symptoms. Since 1993, direct genetic testing has been available, which provides predictive diagnosis even in neurologically asymptomatic persons at risk. The prediction of this devastating disease constitutes a massive psychological burden. In particular, since possibilities of prevention or causal therapy are still not known, ethical aspects are of considerable importance. This refers for example to preimplantation diagnostic testing or the testing of children. Besides, it is important to consider paranoid or depressive symptoms restricting the competence of decision making for genetic testing. Early-onset cognitive deficits may also lead to fundamental disability in understanding. In addition, informed consent may be complex due to social or familial issues which may interfere with the autonomy of the applicant. In these circumstances, the counselor may clash between the principle of beneficence/nonmaleficence and respect for the autonomy of the applicant. In the future, genetic tests will be used for an increasing number of inherited diseases; it is therefore necessary to learn from experiences in the predictive testing of Huntington's disease and to develop ethical codices that can be transferred to the practice of counseling in other genetic disorders.

Adolescent↗
PubMed2003

[Pathology and genetic hereditary kidney cysts].

The classification of cystic kidney diseases according to the pathologic-anatomic potter classification may be difficult. New molecular genetic findings are important to understand the underlying pathogenesis, but less useful to classify the hereditary diseases. An exact classification of polycystic kidney disease in fetus and children is very important for the human genetic consultation. Therefore, the investigation of pathological anatomy of kidney and liver, as well as the evaluation of additional malformations and family history is necessary. For clinical use the mode of inheritance (autosomal dominant and autosomal recessive) is used to differentiate hereditary polycystic kidney diseases.

Humans↗
PubMed2003

Relation between the angiotensinogen (AGT) M235T gene polymorphism and blood pressure in a large, homogeneous study population.

The aim of this study was to assess the association of the angiotensinogen M235T polymorphism with arterial blood pressure (BP) at rest and under physical stress in a homogeneous large-scale study population. In all, 1903 men who passed routine medical examination for military flying duty were recruited. BP and heart rate were measured at rest, during, and after bicycle ergometry. Genotyping for the AGT M235T polymorphism was carried out by PCR and RFLP technique. The AGT T235 allele was associated with a significantly higher diastolic BP (n=1903; MM 81+/-8, MT 83+/-7, TT 83+/-8; P=0.003). Pulse pressure (PP) at rest differed significantly between AGT genotypes (n=1903; MM 51+/-10 mmHg, MT 49+/-10 mmHg, TT 49+/-10 mmHg; P=0.001). During physical activity, BP values showed no significant difference between genotypes. In healthy young men, the AGT T235 allele is significantly associated with elevated diastolic BP but also reduced PP at rest. During physical activity, the AGT polymorphism had no impact on blood pressure, indicating the existence of other counteracting mechanisms, which might balance the influence of this gene.

Adult↗
PubMed2003

Vitamin D receptor gene polymorphism BsmI is not associated with the prevalence and severity of CAD in a large-scale angiographic cohort of 3441 patients.

BACKGROUND: Recent studies found a relationship between Vitamin D and atherosclerosis. A common genetic polymorphism of the Vitamin D receptor (VDR) has been associated with coronary artery disease (CAD) in small study populations. To assess its influence on the prevalence and severity of CAD we studied a large-scale population. METHODS: A total of 3441 consecutive patients were referred for diagnostic coronary angiography. The BsmI Vitamin D receptor polymorphism was analyzed by polymerase chain reaction. Angiography was used to define phenotypes with clear coronary arteries (n = 775), coronary sclerosis (diameter stenosis < 50%; n = 579), CAD (diameter stenosis > 50% in at least one vessel; n = 1524). Patients with CAD at a young age (females aged less than 65 years, males aged less than 55 years; n = 563) were specially defined as premature CAD. The risk profile of traditional cardiovascular risk factors was obtained for every patient. RESULTS: The genotype frequencies of the VDR BsmI polymorphism did not differ between all four phenotypes (P = 0.756). The allele frequencies for the B allele were 0.43 vs. 0.44 vs. 0.42 vs. 0.45 in the four phenotypic groups (P = 0.827). All traditional cardiovascular risk factors (hypercholesterolaemia, smoking, hypertension, diabetes mellitus, severe obesity, male gender) were significantly (P < 0.001) associated with the angiographic phenotype. CONCLUSIONS: The VDR gene variant BsmI was not associated with prevalence and severity of CAD in a large-scale cohort phenotyped by angiography.

Aged↗
PubMed2003

Behavioural problems in children and adolescents with spinal muscular atrophy and their siblings.

Spinal muscular atrophy (SMA) is a chronic illness characterized by loss of motor function. The aim of the study was to investigate behavioural adjustment in 96 children and adolescents with SMA (47 males, 49 females; mean age 11 years 2 months, range 6 to 18 years). Forty-five non-affected siblings (26 males, 19 females; mean age 11 years 6 months, range 6 to 18 years) and 59 normally developing children (33 males, 26 females; mean age 10 years 8 months, range 6 to 18 years) were recruited as control participants. Behavioural symptoms were measured with the Child Behaviour Checklist (CBCL) and disorders were assessed with a structured psychiatric interview (Kinder-DIPS). Of the patients with SMA, 12.5% fulfilled the criteria for an ICD-10 or DSM-IV diagnosis, with separation anxiety disorder being the most common diagnosis. The CBCL total score was in the clinical range for 11.5% of patients, 20% of the siblings, and 11.7% of the control children; the externalizing score rates were 2.1%, 22.2%, and 11.9% respectively; the internalizing score 18.9%, 24.4%, and 13.6% respectively. Comorbid psychopathology was not influenced by sex, IQ, nor severity of SMA, and only externalizing behaviour was correlated to age. In conclusion, children and adolescents with SMA are characterized by a low psychiatric comorbidity not different from control individuals. The group with the highest rate of behavioural problems and with the greatest need for intervention were the non-affected siblings who had a two- to threefold higher rate of behavioural problems than the normative population.

Adolescent↗
PubMed2003

Genetic variations of the SLC7A9 gene: allele distribution of 13 polymorphic sites in German cystinuria patients and controls.

Cystinuria is a hereditary disorder of cystine and dibasic amino acid transport across the luminal membrane of renal tubules and intestine, resulting in recurrent nephrolithiasis. While mutations in the SLC3A1 gene cause type I cystinuria, patients with non-type I cystinuria carry mutations in the SLC7A9 gene. Both gene products form the renal amino acid transporter rBAT/b0,+AT affected in cystinuria. In the present study a total of 59 patients with different ethnic background were screened for sequence variations in SLC7A9, out of these 32 were of German origin. For determination of allele frequencies of detected polymorphisms, 58 healthy German controls were investigated. Molecular-genetic analysis was performed using single-strand conformation polymorphism analysis, restriction assays and sequencing. Allele frequencies were analyzed statistically for the detected polymorphisms. In addition to the 6 already known variants we identified 7 new polymorphisms. Statistical analyses showed a significantly different distribution of alleles between German patients and German controls in case of the polymorphisms c. 147C>T (exon 2), c.386C>T (exon 3), IVS3+22T>G, c.584C>T (exon 4), c.610T>C (exon 4), c.692C>T (exon 5), c.852C>A (exon 6) and c.872C>T (exon 6). In summary, our results show that cystinuria is a complex disease which is not only caused by mutations in SLC7A9 and SLC3A1, but also influenced by other modifying factors such as variants in SLC7A9.

Alleles↗
PubMed2002

Intelligence and cognitive function in children and adolescents with spinal muscular atrophy.

Spinal muscular atrophy is a chronic disease characterised by loss of motor function. The aim of the study was to analyse cognitive functions in a large group of patients with spinal muscular atrophy. It was hypothesised that their intelligence is comparable to controls, but not above average as previously postulated. Ninety-six children and adolescents with spinal muscular atrophy I-III, aged 6.0-18.11 years, 45 non-affected siblings and 59 healthy, matched controls were examined with one- (CPM/SPM), as well as multi-dimensional intelligence tests (Kaufman-ABC; Wechsler tests). The mean IQ measured with the CPM/SPM tests was 109.6 for the spinal muscular atrophy group, 107.3 for the sibs and 104.1 for the healthy controls (no significant difference). In the older children and adolescents (SPM only) the mean IQ was significantly higher for the spinal muscular atrophy patients (109.6) than for the controls (95.4). The standard score in the 'mental processing composite' scale of the Kaufman-ABC was identical in the spinal muscular atrophy group and controls (103.8). The cognitive profile was relatively homogeneous. However, the older children and adolescents did have a significantly higher verbal IQ (113.8) than controls (104.6) in the Wechsler tests. There were no significant differences in any of the tests among different grades of severity (spinal muscular atrophy types I-III). It can be concluded that children and adolescents with spinal muscular atrophy have a general intelligence in the normal range. By adolescence, environmentally mediated aspects of intelligence are higher in patients with spinal muscular atrophy. It could be speculated that the development of cognitive skills and knowledge is a creative way to compensate the many restrictions due to their physical handicap.

Adolescent↗
PubMed2002

Psychopathology and familial stress - comparison of boys with Fragile X syndrome and spinal muscular atrophy.

BACKGROUND: Chronic illness and mental retardation are both associated with an increased rate of behavioural problems in children and with considerable emotional strain in families. The aim of the study was to analyse and compare the specific effects of two exemplary conditions on familial stress and coping. METHODS: Forty-nine boys with Fragile X syndrome (FXS) were compared with 46 boys with Spinal Muscular Atrophy (SMA) and 32 male controls. Intelligence was measured with the RAVEN or K-ABC tests. Psychopathology was assessed with the CBCL questionnaire and a structured psychiatric interview (Kinder-DIPS), parental stress with the QRS, coping with the F-COPES and social support with the F-SOZU questionnaires. RESULTS: The mean age of the FXS boys was 8.6, of the SMA boys 12.7 and of the controls 11.2 years. The mean IQ was 47 for the FXS, 112 for the SMA and 103 for the control groups. According to the CBCL, 89.8% of the FXS boys, 21.7% of the SMA and 15.7% of the controls had a total score in the borderline or clinical range. The rates were 63.3%, 34.8% and 21.9% for internalising and 67.3%, 10.9% and 18.8% for externalising behaviour, respectively. 81.6% of the FXS and 10.9% of the SMA patients had a DSM-IV or ICD-10 psychiatric diagnosis. The most common were ADHD (FXS: 36) and Separation Anxiety Disorder (SMA: 4). In total, parental stress was significantly higher in the FXS than in the SMA families (and in both compared to controls). There were no major inter-group differences regarding social support and familial coping. CONCLUSIONS: Children with FXS are severely mentally retarded and have a high rate of mainly externalising disorders. Despite good coping abilities and social support, this is associated with high familial stress. The SMA boys, with an intelligence in the upper normal range, are no more deviant than their healthy controls. Parental stress is lower in the SMA families with good coping abilities. In conclusion, families with mentally retarded children are in even greater need of help than those of children with severe chronic illness/physical handicap.

Adaptation, Psychological↗
PubMed2002

Analysis of the genes SLC7A9 and SLC3A1 in unclassified cystinurics: mutation detection rates and association between variants in SLC7A9 and the disease.

Cystinuria is a common inherited disorder of defective renal reabsorption of cystine and dibasic amino acids. Recently, 2 responsible genes have been identified: mutations in the SLC3AI gene encoding the glycoprotein rBAT cause cystinuria type I, while variants in the SLC7A9 gene have been demonstrated in non-type I cystinuria; its gene product b(0)+AT is the light chain of the renal cystine transport system rBAT/b(0),+-AT. To estimate the role of both genes in the etiology of cystinuria, we searched for sequence alterations in SLC7A9 and SLC3AI: 30 unclassified cystinurics were investigated. In 50% of patients (15/30), point mutations in SLC3A1 were detected. Screening of the SLC7A9 gene revealed 10 mutations in 8 patients corresponding to a frequency of 27%. In addition to previously published mutations in the SLC7A9 gene, we detected 2 new mutations (F 140S, c747delG). An overall detection rate of 73% (22/30) in unclassified patients is delineated for mutations in both genes. In 33% (10/30), 2 mutations were detected, in 40% (12/30) 1 mutation. Furthermore, 5 new polymorphic sites were identified in SLC7A9. While the base pair variation in intron 9 is homogeneously distributed in patients and control individuals, the allelic and genotypic distributions of the polymorphisms in 3 exons of SLC7A9--exons 2, 5 and 6--and intron 3 differ significantly between both groups. Our results suggest that some haplotypes defined through the exons 2, 5 and 6 and intron 3 might be markers of a functional variant in the SLC7A9 gene. Evidently, since the mutation detection rates in the 2 so far known cystinuria genes never reach 100%, further genes and modulating factors should influence the phenotype in a subset of patients. However, the presented data show that testing for mutations in the 2 currently known cystinuria genes is already a meaningful approach to the molecular diagnostics of the disease.

Amino Acid Transport Systems, Basic↗
PubMed2001

Phenotypic variation of a novel nonsense mutation in the P0 intracellular domain.

Mutations in the gene for the peripheral myelin protein zero (P0, MPZ) cause type 1B of Charcot-Marie-Tooth sensorimotor neuropathy (CMT1B). Here we report a German family with a novel heterozygous P0 nonsense mutation (G206X) that supposedly removes four-fifths of the amino acid residues constituting the P0 intracellular domain. The 12-year-old propositus had childhood-onset CMT1B associated with bilateral pes cavus, moderate lower limb weakness, and mildly reduced sensory qualities in the distal legs. The electrophysiology was consistent with a demyelinating neuropathy. He inherited the mutation from his mother who had no complaints but slight pes cavus deformity and slow nerve conduction velocities (NCV). Conclusively, truncating mutations within the P0 intracellular domain do not necessarily cause a severe phenotype such as Dejerine-Sottas syndrome (DSS) or congenital hypomyelinating neuropathy (CHN), but can result in mild or moderate CMT1B with intrafamilial clinical variability.

Adult↗
PubMed2001

A point mutation in the human connexin32 promoter P2 does not correlate with X-linked dominant Charcot-Marie-Tooth neuropathy in Germany.

The sensorimotor neuropathy Charcot-Marie-Tooth disease (CMT) is the most common hereditary disorder of the peripheral nervous system. The X-linked dominant form of CMT (CMTX) is associated with mutations in the connexin32 gene (Cx32). The majority of CMTX cases harbour mutations in the coding region while a few cases have been reported to result from mutations in the promoter region. We found a G-713A transition of the nerve specific Cx32 promoter P2 in the Caucasian German population. The allele frequency reached 50%, both in CMT patients and in healthy control individuals. In contrast, in an earlier contribution to this journal [Brain Res. Mol. Brain Res.78 (2000) 146], the same base transition was reported to cause CMTX in a Taiwanese family. These divergent results are important for genetic counselling and require careful consideration of ethnic backgrounds and of diagnostic and experimental pitfalls.

Charcot-Marie-Tooth Disease↗
PubMed2001

A novel neurodevelopmental syndrome responsive to 5-hydroxytryptophan and carbidopa.

Tryptophan hydroxylase (TPH; EC 1.14.16.4) catalyzes the first rate-limiting step of serotonin biosynthesis by converting l-tryptophan to 5-hydroxytryptophan. Serotonin controls multiple vegetative functions and modulates sensory and alpha-motor neurons at the spinal level. We report on five boys with floppiness in infancy followed by motor delay, development of a hypotonic-ataxic syndrome, learning disability, and short attention span. Cerebrospinal fluid (CSF) analysis showed a 51 to 65% reduction of the serotonin end-metabolite 5-hydroxyindoleacetic acid (5HIAA) compared to age-matched median values. In one out of five patients a low CSF 5-methyltetrahydrofolate (MTHF) was present probably due to the common C677T heterozygous mutation of the methylenetetrahydrofolate reductase (MTHFR) gene. Baseline 24-h urinary excretion showed diminished 5HIAA values, not changing after a single oral load with l-tryptophan (50-70 mg/kg), but normalizing after 5-hydroxytryptophan administration (1 mg/kg). Treatment with 5-hydroxytryptophan (4-6 mg/kg) and carbidopa (0.5-1.0 mg/kg) resulted in clinical amelioration and normalization of 5HIAA levels in CSF and urine. In the patient with additional MTHFR heterozygosity, a heterozygous missense mutation within exon 6 (G529A) of the TPH gene caused an exchange of valine by isoleucine at codon 177 (V177I). This has been interpreted as a rare DNA variant because the pedigree analysis did not provide any genotype-phenotype correlation. In the other four patients the TPH gene analysis was normal. In conclusion, this new neurodevelopmental syndrome responsive to treatment with 5-hydroxytryptophan and carbidopa might result from an overall reduced capacity of serotonin production due to a TPH gene regulatory defect, unknown factors inactivating the TPH enzyme, or selective loss of serotonergic neurons.

5-Hydroxytryptophan↗
PubMed2001

Phaeochromocytoma associated with a de novo VHL mutation as form fruste of von Hippel-Lindau disease.

UNLABELLED: Phaeochromocytomas usually occur sporadically but may be associated with dominant inherited cancer syndromes such as multiple endocrine neoplasia type 2 (MEN 2), von Hippel-Lindau disease (VHL) and type 1 neurofibromatosis. We report on a boy presenting at age 8 years with an isolated benign phaeochromocytoma of the left adrenal. Three years later a second adrenal phaeochromocytoma was diagnosed on the right side and removed. His family history was negative. Genetic analysis did not show a mutation in the MEN 2 susceptible proto-oncogene rearranged during transfection; however, we found a germline missense mutation in the VHL gene (nucleotide 695 G to A transversion) which has been described only twice before in the literature. Both parents had normal (wild type) VHL copies indicating that our patient had a de novo germline VHL mutation. Careful clinical evaluation of the patient at 18 years did not reveal any other manifestations of VHL disease. CONCLUSION: Carriers of von Hippel-Lindau germline mutations can present with a form fruste of von Hippel-Lindau disease presenting initially with unilateral phaeochromocytoma and therefore mutation analysis should be carried out.

Adrenal Gland Neoplasms↗
PubMed2001

Mutations in the gene encoding immunoglobulin mu-binding protein 2 cause spinal muscular atrophy with respiratory distress type 1.

Classic spinal muscular atrophy (SMA) is caused by mutations in the telomeric copy of SMN1. Its product is involved in various cellular processes, including cytoplasmic assembly of spliceosomal small nuclear ribonucleoproteins, pre-mRNA processing and activation of transcription. Spinal muscular atrophy with respiratory distress (SMARD) is clinically and genetically distinct from SMA. Here we demonstrate that SMARD type 1 (SMARD1) results from mutations in the gene encoding immunoglobulin micro-binding protein 2 (IGHMBP2; on chromosome 11q13.2-q13.4). In six SMARD1 families, we detected three recessive missense mutations (exons 5, 11 and 12), two nonsense mutations (exons 2 and 5), one frameshift deletion (exon 5) and one splice donor-site mutation (intron 13). Mutations in mouse Ighmbp2 (ref. 14) have been shown to be responsible for spinal muscular atrophy in the neuromuscular degeneration (nmd) mouse, whose phenotype resembles the SMARD1 phenotype. Like the SMN1 product, IGHMBP2 colocalizes with the RNA-processing machinery in both the cytoplasm and the nucleus. Our results show that IGHMBP2 is the second gene found to be defective in spinal muscular atrophy, and indicate that IGHMBP2 and SMN share common functions important for motor neuron maintenance and integrity in mammals.

Amino Acid Sequence↗
PubMed2001

Enuresis and urinary incontinence in children and adolescents with spinal muscular atrophy.

OBJECTIVE: To assess the rate and type of urinary incontinence in a large sample of children and adolescents with spinal muscular atrophy (SMA), a genetic disorder characterized by loss of motor function caused by anterior horn degeneration. PATIENTS, SUBJECTS AND METHODS: The study included 96 severely incapacitated patients with SMA (aged 6.0-18.11 years) who were examined in detail, including a structured interview (Kinder-DIPS), the Child Behaviour Checklist (CBCL) and a specific questionnaire for urinary incontinence. They were compared with two control groups of unaffected siblings and normal children. RESULTS: In all, 29% of the patients were wet at night and/or during the day; mostly younger children with SMA types I and II only were affected. The results of the interview were more reliable than the CBCL. The specific questionnaire revealed a variety of possible functional and neurogenic forms of wetting, including nocturnal enuresis, voiding postponement, dysfunctional voiding, stress, symptomatic (urinary tract infections, UTIs) and neurogenic incontinence. Many patients were constipated, soiled or had UTIs. The rate of behavioural problems was twice as high (32%) as normal (15%; CBCL). CONCLUSION: Children with SMA have a high rate of urinary incontinence which is often overlooked, and not diagnosed and treated adequately. These problems should be addressed routinely by paediatricians in children referred to paediatric urological specialists.

Adolescent↗
PubMed2001

Neurodevelopmental risks in twin-to-twin transfusion syndrome: preliminary findings.

The purpose of this study was to determine the neurodevelopmental risks in patients with twin-to-twin transfusion syndrome, a rare but serious complication of monochorionic twin gestations. From a total sample of 94 twins with twin-to-twin transfusion syndrome, admitted during 1989 and 1993, 49 patients survived and 40 patients were followed to a mean age of 24 months. Neurological status and psychomotor development (Denver and Griffiths Developmental Tests) were determined. Parameters of the neonatal period were evaluated for their potential prediction. Of the 40 tested patients 18 showed a normal psychomotor development. Thirteen patients exibited a specific delay in language development and/or showed minor neurological dysfunctions. Nine twins had severe psychomotor retardation in combination with cerebral palsy. Major neurological sequelae were found, more common in recipients than in donors (6/19 vs 3/21). Correspondingly, neonatal ultrasound showed more pathological results (especially periventricular leucomalacia) in recipients. Neither anaemia nor polycythaemia at birth can predict developmental outcome. Apart from a high prenatal mortality rate, both twins, donators as well as recipients, are highly at risk for brain damage of different aetiology, associated with abnormal neonatal cerebral ultrasound.

Birth Weight↗